In this bash script tutorial you will learn the basics to create bash scripts.
Bash Script Environment
In this bash script tutorial I am using Linux. But you can also use a Mac and perhaps Windows.
Bash Script Linux
My preference is creating bash scripts in Linux. Although I have the feeling that if you are in Linux you already know some Bash :)
If you are not using Bash. Maybe you know some Linux commands? If not no problem. First find where
bash is installed in your system.
Open the terminal and type:
It might say:
If you are on Mac it might say:
Keep this in mind for later.
Vim Text Editor
I love Vim because it has a mouse free environment and helps you become hyperfocused. Although Vim has kind of a steep learning curve.
Installing Vim on Ubuntu Linux:
sudo apt install vim
Installing Vim on Fedora Linux:
sudo dnf install vim
Installing Vim on Mac:
brew install vim
Although keep in mind that for the Mac to use
brew you need to install
homebrew. Just go to Homebrew and copy paste the command shown on the homepage into the terminal.
Sublime Text Editor
Sublime is less geek and it looks just like any program. You can download it from here.
Bash Script Windows
What I recommend is to install Linux using Virtualbox. A video will soon be posted here.
Bash Script Basics
Create a new file either and save it as
awesome-file.sh. Yeah it ends with
In the first line type in the location of bash.
For Linux bin bash is often:
For Mac bin bash is often:
#! is called a
shebang or a
What follows the
shebang is the location of bash binaries. In other words it tells the file what you want to execute the file with Bash.
Bash script simple silly example
It’s downhill from here :)
Below the bin bash line enter a new line and add this line:
With bin bash on Linux:
#!/bin/bash echo "Hello"
Or with bin bash on Mac:
#!/usr/local/bin/bash echo "Hello"
Save and close the file.
Change the bash script file to execute
Go back to the terminal and change directories to where the file is.
Type this command to make the bash script executable:
chmod +x awesome-file.sh
Execute this simple silly bash script example
On the terminal type this to execute this bash script example:
This means to execute in the current directory.
The result should be:
These are other advanced examples
How to declare variables and initialize some to zero.
declare -i filenumber=0 declare -i sponsornumber=0 declare -i counter=0 declare -i directory_size
Assign a string to a variable
Calculate the directory size where the files are stored
directory_size="$(ls -l ./ | grep 'jpg' | wc -l)"
Rename files in the directory to a random number
for file in *.jpg; do number="$RANDOM" mv "$file" "$number$filetype" done
Use a random number within a range
Random number from 1 to 10:
number="$(((RANDOM % 10) + 1))"
Random number from 1 to 100:
number="$(((RANDOM % 100) + 1))"
Rename files into a sequential number 1, 2, 3…etc
for file in *.jpg; do filenumber="$(($filenumber + 1))" mv "$file" "$filenumber$filetype" done